1. Field of the Invention
The invention relates to the bleaching of textiles. More particularly, it relates to a process for the carrying out of such textile bleaching in an improved, more economical manner than in conventional processing.
2. Description of the Prior Art
The ability of oxygen to bleach textiles was discovered centuries ago as a result of the exposure of cloth to the ambient environment of air and sunlight. While this type of bleaching action is effective and economical, it is also quite slow and thus unsuited for industrial applications. Modern textile bleaching is generally carried out chemically using hydrogen peroxide as the bleaching agent because of its quick and thorough bleaching or whitening action. However, hydrogen peroxide is also very expensive and tends to degrade very rapidly at the high temperatures necessary for the proper bleaching of textiles.
In a typical textile bleaching plant employing the conventional hydrogen peroxide bleaching process, cloth is first treated with caustic and is then passed into a bleach tank containing a bleaching solution consisting of hydrogen peroxide, water and a stabilizing agent at 37.degree. C. The hydrogen peroxide concentration is typically about 1.5% by weight. The cloth is then passed from the bleach tank through a heater tube in which it is heated to about 90.degree.-99.degree. C. It is then folded into a tortuous shape and passed into a well insulated vessel, referred to as a "J box" because of its typical shape, wherein the desired contact time is provided between the cloth being bleached and the hydrogen peroxide in the bleaching solution. The residence time in the J-box is typically about 60-90 minutes.
As in other industrial processing operations, there is always a desire in the art for improvements in such conventional textile bleaching operations. This is particularly the case because of the cost and degradation characteristics of the hydrogen peroxide bleaching agent. While other bleaching agents are known in the art, hydrogen peroxide is generally preferred, despite such disadvantages, because of its highly advantageous bleaching properties and because alternative bleaching agents likewise have economic and processing disadvantages.
It is an object of the invention, therefore, to provide an improved process for the bleaching of textiles with hydrogen peroxide.
It is another object of the invention to provide a process in which the hydrogen peroxide bleaching of textiles can be carried out in a more efficient and effective manner.
With these and other objects in mind, the invention is hereinafter described in detail, the novel features thereof being particularly pointed out in the appended claims.